To increase their output, many individual PV cells can be connected together in a sealed, weatherproof package called a module. When two modules are wired together in series, their voltage is doubled while the current stays constant. When two modules are wired in parallel, their current is doubled while the voltage stays constant. To achieve the desired voltage and current, modules are wired in series and parallel into what is called a PV array.

Figure 14a Series circuit	Figure 14b Parallel circuit	Figure 14c Series and parallel circuit